Ink jet recording method

Abstract

An ink jet recording method capable of providing an image having a good quality is disclosed. In the ink jet recording method, a reaction solution and an ink composition are used to conduct printing on a recording medium. The reaction solution comprises a polyvalent metal salt, and an ink composition comprises a pigment and a resin emulsion.

What is claimed is: 
     
       1. An ink jet recording method comprising the steps of providing a reaction solution comprising a polyvalent metal salt, and an ink composition comprising a pigment and a resin emulsion; and depositing the reaction solution and the ink composition onto a recording medium. 
     
     
       2. An ink jet recording method according to claim 1 comprising the steps of providing a reaction solution comprising a polyvalent metal salt, and an ink composition comprising a colorant and an alginic acid derivative; and depositing the reaction solution and the ink composition onto a recording medium. 
     
     
       3. The ink jet recording method according to claim 2, wherein the alginic acid derivative is an alkali metal salt of alginic acid or an ammonium salt of alginic acid. 
     
     
       4. The ink jet recording method according to claim 2, wherein the ink composition comprises 0.01 to 1% by weight of the alginic acid derivative. 
     
     
       5. The ink jet recording method according to claim 2, wherein the ink composition comprises a colorant, an organic solvent, water, and a resin emulsion. 
     
     
       6. An ink jet recording method comprising the steps of providing a reaction solution comprising a polyvalent metal salt, and an ink composition comprising water and a pigment, and depositing the reaction solution and the ink composition onto a recording medium to form a print thereon, wherein the ink composition comprises a resin emulsion in an amount sufficient to improve an optical density or evenness of the print formed on the recording medium as compared to the print formed with the ink composition without the resin emulsion. 
     
     
       7. An ink jet recording method according to claim 6, wherein the resin emulsion is present in the ink composition in an amount of from 0.1 to 40% by weight. 
     
     
       8. An ink jet recording method according to claim 7, wherein the resin emulsion is present in the ink composition in an amount of from 1 to 25% by weight. 
     
     
       9. An ink jet recording method according to claim 7, wherein the pigment is present in the ink composition in an amount of about 0.5 to 25% by weight. 
     
     
       10. An ink jet recording method according to claim 7, wherein the ink composition further comprises an alginic acid derivative in an amount of about 0.01 to 1% by weight. 
     
     
       11. An ink jet recording method according to claim 10, wherein the ink composition further comprises an organic solvent. 
     
     
       12. An ink jet recording method according to claim 11, wherein the alginic acid derivative is an alkali metal salt of alginic acid or an ammonium salt of alginic acid. 
     
     
       13. An ink jet recording method according to claim 6, wherein the reaction solution further comprises a polyol having an vapor pressure of not more than 0.01 mmHg at 20° C., wherein the content of the polyol is such that the weight ratio of the polyol to the polyvalent metal salt is 1 or more. 
     
     
       14. The ink jet recording method according to claim 13, wherein the polyol is selected from glycerin, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,4-butandiol, and a saccharide. 
     
     
       15. The ink jet recording method according to claim 13, wherein the ink composition comprises not less than 10% by weight of the polyol. 
     
     
       16. The ink jet recording method according to claim 6, wherein the reaction solution has a surface tension of not more than 35 mN/m, and wherein the ink composition has a surface tension of not more than 40 to 50 mN/m. 
     
     
       17. The ink jet recording method according to claim 16, wherein the reaction solution has a surface tension of 25 to 35 mN/m, and the ink composition has a surface tension of 40 to 50 mN/m. 
     
     
       18. The ink jet recording method according to claim 16, wherein the reaction solution and the ink composition each have a viscosity of 1.5 to 10 mPa.s at 20° C. 
     
     
       19. The inkjet recording method according to claim 6, wherein the resin emulsion comprises a thermoplastic resin with a softening temperature, the method further comprising the step of heating the recording medium with the ink composition deposited thereon to the softening temperature of the thermoplastic resin or a higher temperature. 
     
     
       20. The ink jet recording method according the claim 19, wherein the step of heating is carried out at a given period after the deposition of the droplets of the ink composition onto the recording medium. 
     
     
       21. The ink jet recording method according to claim 19, wherein the resin emulsion has a film forming temperature and the heating temperature is at least the film forming temperature of the resin emulsion. 
     
     
       22. The ink jet recording method according to claim 6, wherein the polyvalent metal salt is composed of nitric acid ion or a salt of carboxylic acid ion and polyvalent metal ion. 
     
     
       23. The ink jet recording method according to claim 22, wherein the carboxylic acid ion is derived from a saturated aliphatic monocarboxylic acid having 1 to 6 carbon atoms, wherein at least one hydrogen atom on a saturated aliphatic hydrocarbon residue of the monocarboxylic acid is optionally substituted by a hydroxyl group, or a carbocyclic monocarboxylic acid having 6 to 10 carbon atoms. 
     
     
       24. The ink jet recording method according to claim 22, wherein the reaction solution comprises triethylene glycol monobutyl ether and glycerin. 
     
     
       25. The ink jet recording method according to claim 22, wherein the colorant contained in the ink composition is a pigment. 
     
     
       26. The ink jet recording method according to claim 6, wherein the reaction solution is a color ink containing a colorant selected from the group consisting of yellow, cyan, and magenta colorant. 
     
     
       27. The ink jet recording method according to claim 6, wherein the reaction solution contains a penetrating agent. 
     
     
       28. The ink jet recording method according to claim 27, wherein the penetrating agent is a compound represented by the following formula (I) and/or a lower alcohol ether of a polyhydric alcohol: ##STR3## wherein 0≦m+n≦50 and R 1 , R 2 , R 3 , and R 4  each independently represents an alkyl group. 
     
     
       29. The ink jet recording method according to claim 6, wherein the reaction solution is first deposited onto the recording medium and the ink composition is then deposited onto the recording medium. 
     
     
       30. The ink jet recording method according to claim 6, wherein the ink composition is first deposited onto the recording medium and the reaction solution is then deposited onto the recording medium. 
     
     
       31. The ink jet recording method according to claim 6, wherein the reaction solution and the ink composition are mixed together immediately before or immediately after the depositing.